Activated Protein C Resistance(APC-R)

The Activated Protein C Resistance (APC-R), Plasma test evaluates how the body responds to activated protein C, a natural protein that helps regulate blood clotting. Resistance to activated protein C can increase the tendency to form abnormal blood clots and is commonly associated with the Factor V Leiden mutation, an inherited clotting disorder. This test helps doctors investigate the underlying cause of recurrent or unexplained blood clots and assess an individual’s risk for thrombophilia.

Who Should Get This Test Done?

This test may be recommended if individuals:

●     Have experienced deep vein thrombosis (DVT), pulmonary embolism (PE), recurrent blood clots, or clotting events without an obvious cause, particularly at a young age.

●     Have a family history of Factor V Leiden mutation, unexplained thrombosis, or other inherited clotting disorders.

●     Have had pregnancy-related complications such as recurrent miscarriages, stillbirths, severe preeclampsia, or blood clots during pregnancy.

●     Are pregnant, planning a pregnancy, or considering oral contraceptives or hormone replacement therapy and have risk factors for thrombosis.

●     Have developed blood clots in unusual locations, experienced recurrent thrombosis despite treatment, or require a thrombophilia evaluation before major surgery or prolonged immobilisation.

Why Consider This Test?

This test can be considered because it helps evaluate the body’s response to activated protein C, an important regulator of blood clotting. It aids in identifying individuals with an increased tendency to develop abnormal blood clots, supports the evaluation of inherited clotting disorders such as Factor V Leiden, and helps doctors determine the underlying cause of unexplained or recurrent clotting events. The test also provides useful information for further investigations and appropriate clinical management as part of a comprehensive thrombophilia assessment.

More Information

Activated protein C plays a key role in maintaining the balance between clot formation and clot breakdown. When the body becomes resistant to its action, the normal control of blood clotting may be affected, increasing the likelihood of unwanted clot formation. The APC-R test is often performed along with other coagulation and thrombophilia tests to provide a more complete assessment. The results are interpreted in combination with a person’s medical history, family history, and other laboratory findings.

Other Names

The Activated Protein C Resistance, Plasma test may also be referred to as:

●     APC Resistance Test

●     Activated Protein C Resistance Assay

●     APC Resistance Ratio Test

●     Factor V Leiden Functional Screen

●     Factor V Resistance Test

●     Thrombophilia Screening – APC Resistance

●     Coagulation APC Resistance Test

●     Functional Factor V Leiden Test

●     Hereditary Thrombophilia APC Resistance Test